Improving Software Development Efficiency through Lean Practices and DevOps at Youzan

Background: Lean manufacturing emphasizes respect for people, waste elimination, and continuous improvement. The seven classic wastes (overproduction, waiting, transport, inventory, processing, extra motion, defects) plus management waste are applied to software development.

The Youzan Efficiency Improvement team adopts lean principles to reduce waste and boost R&D efficiency. While project‑based management is common, engineering practices remain fragmented across departments, lacking a unified platform.

1. Current Engineering Practice

1.1 Technical Debt

Youzan, as a fast‑growing startup, prioritized market survival over technical foundation, leading to accumulating technical debt. Unaddressed debt increases maintenance cost and creates legacy code that is hard to modify.

From a lean perspective, technical debt is an "extra motion" waste. The team needs to quantify debt, assess risk, and estimate remediation cost. SonarQube static analysis was used to visualize code quality (see image).

1.2 Impact of Code Changes

Garbage in, garbage out – incremental development on debt‑laden code is risky. Over‑commented files can be more cumbersome than the code itself, and defects often surface in production.

Illustrated by the cover of "The Phoenix Project", the situation highlights the danger of hidden defects.

1.3 Integration Cycle

Software development requires multi‑party collaboration. While individual code quality may be high, large‑scale integration often fails, representing the "waiting" waste in lean.

Delays in integration, uncommunicated interface changes, and prolonged build times are shown in the DevOps platform metrics (see image).

2. Efficiency Improvement Entry Points

2.1 Concept Introduction

The team identified continuous integration (CI) as a high‑leverage point, with automated unit testing and environment governance as prerequisites.

Three key practices were promoted:

High‑coverage, high‑quality unit tests protect business logic without extra testing cost.

Stable test environments trigger static analysis and unit tests automatically on code commits.

Integrated test suites enable unattended continuous integration, automated packaging, deployment, and verification.

2.2 Volunteer Pilot

A willing pilot group (U team) was selected, with strong support from technical leads. Additional enthusiastic contributors (S team, Z team) helped create and share best practices for unit testing.

2.3 Side‑Support

Collaboration among development, quality assurance, and operations teams reinforced the practice. QA enforced test‑coverage gates, while operations standardized dev/QA/pre environments.

Metrics show increasing test‑coverage compliance across business lines (see image).

2.4 Tool Support

Youzan’s self‑built "Performance Platform" integrates with the DevOps system, providing one‑click environment provisioning, status synchronization, and automated gating based on thresholds.

Partial view of the continuous delivery pipeline is shown (see image).

2.5 Culture Building

Creative initiatives were introduced to raise awareness:

CI indicator lights built with Raspberry Pi and LEDs flash red when a build fails, prompting immediate attention.

CI big screens display real‑time application status, fostering healthy competition and serving as a visual showcase for visitors.

Photos of the indicator lights, big screen, and visitor interactions are included (see images).

Conclusion

By applying lean thinking to engineering practice—introducing concepts, piloting volunteers, strengthening tools, and creating engaging cultural artifacts—Youzan reduced waste and significantly improved development efficiency.

The combined effort of the efficiency improvement team, QA, and operations demonstrates that systematic process and tool enhancements can embed DevOps principles into the daily workflow.